Metal contents of phosphate rocks

Abstract

Significant amounts of phosphate rocks (PRs) are mined around the world annually. The rocks are either applied directly to soils or manufactured to produce water‐soluble phosphorus (P) fertilizers. In this study, we analyzed 12 PRs obtained from various deposits in Africa, United States, and Peru for total P, ten trace metals [cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), lithium (Li), manganese (Mn), nickel (Ni), lead (Pb), rubidium (Rb), and zinc (Zn)] and eight nontrace metals [aluminum (Al), barium (Ba), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), sodium (Na), and strontium (Sr)]. The empirical formulae and the unit‐cell a dimension of the apatite contents were also determined. Results showed that the values of the unit‐cell a dimension ranged from 9.324 Å for North Carolina PR to 9.365 Å for Tahoua PR. The total P contents ranged from 109 g/kg for Kodjari PR to 176 g/kg for Parc W PR. The concentration of the trace metals in the PRs varied considerably. Expressed in mg/kg PR, the ranges and median values were: Cd (5–47, 10), Co (6–104, 22), Cu (5–41, 8), Cr (18–331, 46), Li (2–9, 2), Mn (11–6553, 263) , Ni (1–61, 10) , Pb (7–43, 14), Rb (3–18, 6), and Zn (54–576, 124). The corresponding values of the nontrace metals expressed in g/kg were: Al (1.7–20.0, 5.6), Ba (0–4.4, 0.4), Ca (211–330, 298), Fe (1.4–45.7, 6.8), K (0.3–10.9, 1.4), Mg (0.6–16.9, 2.2), Na (1.0‐ 22 .8, 10.4), and Sr (0.3–6.7, 1.0). At the detection limit of 5 ng/mL, no cesium (Cs) was found in the PR analyzed.     

Effect of chelate fertilizers on dry matter and metallic composition of bean plants in a pot experiment

Bean plants were grown in pots contaning 6 kg of loamy sandy soil. A basal dose of NPK (150–120–100 kg/ha) fertilizers was mixed with the soil before potting and was repeated when the bean plants were 30 days old. Five different fertilizers and three rates of each fertilizer were investigated in this study. Fertilizers were applied seven days after germination and all treatments were triplicated. Bean plants were harvested 20, 30, and 45 days after sowing, dried, weighed, and digested in nitric‐perchloric acids. Concentrations of 18 elements were determined in the digests using an inductively coupled argon plasma spectrometer. At the end of the experiment, soil samples were also collected and extracted with DTPA. Bean dry matter yield was not significantly (p<0.05) affected by fertilizer application. Concentrations of aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), cobalt (Co), iron (Fe), manganese (Mn), molybdenum (Mo), strontium (Sr), nickel (Ni), titanium (Ti), vanadium (V), and zinc (Zn) were significantly (p<0.05) lower in plant samples collected from the control treatments. Fertilizer application had no significant effect on concentrations of copper (Cu), potassium (K), sodium (Na), magnesium (Mg), phosphorus (P), and lead (Pb) in bean plants. Metal concentrations decreased with an increase in plant age, probably due to dilution effect. DTPA‐extractable concentrations of Co, Fe, Mn, Zn, Pb, Mo, and V were not significantly (p<0.05) correlated to their respective concentrations in bean plants.     

Biophenols in table olives

Unprocessed olives are well-known sources of phenolic antioxidants with important biological properties. Processing methods to prepare table olives may cause a reduction of valuable phenols and may deprive the food of precious biological functions. The present work was undertaken to evaluate table olives produced in Greece as sources of biophenols. Commercially available olives were analyzed for their total phenol content by using the Folin-Ciocalteu reagent and for individual phenols by RP-HPLC. Samples were Spanish-style green olives in brine, Greek-style naturally black olives in brine, and Kalamata olives in brine. Most of the types of olives analyzed were found to be good sources of phenols. Hydroxytyrosol, tyrosol, and luteolin were the prevailing phenols in almost all of the samples examined. High levels of hydroxytyrosol were determined mainly in Kalamata olives and Spanish-style green olives, cultivar Chalkidiki (250-760 mg/kg).     

Absorption of Heavy Metals in Wild Berries and Edible Mushrooms in an Area Affected by Smelter Emissions

The total concentrations of nickel, copper, chromium, strontium, arsenic, lead, cadmium and cobalt were measured in berries and mushrooms, as well as manganese and iron in mushrooms. The study area (about 3500 km²) is situated on the border of the northern taiga and tundra forests (68–69°N) and is affected by emissions from the extensive Ni-Cu smelter complex at Monchegorsk, Kola Peninsula, NW Russia. Part of the study area, extending along the railway line used for transporting apatite concentrate, contains elevated quantity of strontium. Berries of Vaccinium vitis-idaea (82 samples), Vaccinium myrtillus (28), Rubus chamaemorus (42) and Empetrum hermaphroditum (40) and mushrooms of Leccinum auantiacum (47 samples), Leccinum scabrum (32), Russula vesca (25), Lactarius torminosus (8), Lactarius trivialis (9), Suillus luteus (10) and Xerocomus subtomentosus (20 specimens) were collected from 98 locations during 1987–1992. The nickel and copper concentrations in the berries, and nickel in mushrooms, correlated satisfactorily with the corresponding metal concentrations in the soil. The berries and mushroons growing over an area of at least 3000 km² around the smelter complex are unsuitable for human consumption due to the elevated nickel concentrations caused by the smelter dust emissions. The berries and mushrooms gathered in the studied polluted forests were found to be contaminated by nickel by a factor of 15–30 times (berries) and 15–40 times (mushrooms) more than the background level. Increased levels of strontium were found close to the railway line. The concentrations of all the other metals in the studied area did not exceed sanitary standards.     

恩施典型富硒区土壤硒与其他元素组合特征及来源分析

硒是重要的人体和动物必需微量元素之一,在功能农业发展中起着重要的作用。为了研究高硒土壤中硒与其他元素组合特征及来源,从而支撑富硒资源的安全有效利用,本研究在恩施市沙地乡系统采集并分析了200个表层土壤样和2组土壤垂向剖面样品,运用统计学工具进行了聚类分析和因子分析。结果表明:研究区表层土壤硒含量平均值为1.88 mg/kg±2.51 mg/kg,明显高于全国表层土壤硒含量平均值。研究区土壤元素组合特征可分为三类,第一类中硒与钼、钒、铬、镉和镍等元素具有较强的伴生关系,与黑色岩系分布密切相关;第二类为三氧化二铝、铅和砷等元素/氧化物,与土壤中黏土矿物有关;第三类为钙和锶等元素,表明该同族元素的地球化学性质具有相似性。因子分析结果进一步证实了土壤硒和镉伴生主要发生在黑色岩系,不同成土母质硒等元素差异较大。     

Determination of Major and Trace Elements in Plant Samples by Inductively Coupled Plasma–Mass Spectrometry

The determination of several trace elements [arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), molybdenum (Mo), nickel (Ni), and lead (Pb)] in plant samples using inductively coupled plasma–mass spectrometry (ICP‐MS) was evaluated. It was established experimentally that moderate amounts (0.2–2%) of dissolved solids decreased the analyte signals significantly. Internal standardization with Rh was efficiently used to compensate for these matrix effects. The accuracy of the method was verified using reference materials digested according to two different procedures: dry ashing and microwave digestion. No significant differences were observed between measured concentrations and certified values. The investigation was next extended for the determination of major elements [aluminum (Al), boron (B), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), phosphorus (P), and zinc (Zn)] on the same reference materials. The ICP‐MS values agree well with the values supplied. However, it appeared that Sc was the most useful internal standard for major elements.     

Soil Surface Geochemical Anomaly Around the Copper-Nickel Metallurgical Smelter

The soils were sampled from the center of airborne contamination caused by long time activity of a copper/nickel smelter complex in the Kola Peninsula, Russia. The soil specimens were taken from an area about 250 km², which included the town of Monchegorsk, with frequency of 1 sample (plot) per 3 km² and heavy metals nickel, copper, cobalt, chromium, lead, cadmium, strontium, iron, manganese and arsenic were measured. The soil surrounding the Smelter, including the inhabited territory of the town, was found to be contaminated by nickel and copper to levels 450- and 250 times higher in comparison to the background, respectively. These soils were found to be extremely toxic and represented a severe threat to human health. Elevated concentrations of iron and arsenic caused by smelter emissions were found too.     

Vertical Distributions of Trace Metals in Natural Soil Horizons from Japan. Part 1. Effect of Soil Types

To predict the long-term behavior of trace metals in a soilprofile, we studied the vertical distributions of barium, zinc,copper, chromium, nickel, cobalt, lead, and the principalmetals, aluminum, iron and manganese, in three soils withdeveloped horizons obtained from rural areas in Japan. Totalelement analysis and selective extraction tests with variousreagents were conducted to clarify the extractability of themetals at each sampling depth.Soil-b (Dystric Cambisols) had the highest extractability ofelements although the vertical distributions of its traceelements were similar to those of soil-d (Umbric Andosols),which had to lowest metal extractability of the three soils.Soil-KUR (Orthic Acrisols or Dystric Cambisols) was the oldest of the three soils and showed downward movement of some tracemetals (chromium and nickel) and principal elements (Fe and Mn)that was probably induced by long-term weathering.The extractability of manganese, zinc and barium with water washigher than other metals examined in all three soils. Lead andcobalt in soil-b and soil-KUR also were considered to have highextractability under long-term weathering processes. Zinc andlead accumulated near soil surface showed higher extractabilitywith every reagent used than those in deep layers of the three soils.     

Bioaccumulation of Trace and Non-trace Elements in Blood and Fibers of Alpacas (<Emphasis Type="Italic">Vicugna pacos</Emphasis>) that Graze in Italian Pastures

The concentrations of trace and non-trace elements were determined in blood and fibers of alpacas (Vicugna pacos) from a north Italian area, as well as in their pasture forages. This is the first investigation regarding this species in Italy, and the first considering alpaca’s fiber as bioindicator worldwide. Metal contents in blood were in the decreasing order: copper?>?zinc?>?aluminum?>?selenium?>?lead?>?nickel?>?manganese?>?chromium?>?arsenic and cadmium, while in fiber, metal levels were in the following order: aluminum?>?zinc?>?copper?>?manganese?>?chromium?>?nickel?>?selenium?>?lead?>?arsenic and cadmium. Antimony, beryllium, mercury, tin, and thallium were below the limit of quantification (0.010 mg kg^?1). The analysis of the alpacas’ forage confirmed the same trend found in fiber, suggesting that metal bioaccumulation was affected by diet. These preliminary results have shown that all the trace elements studied bioaccumulated to a greater extent in the fibers of the alpaca than in the blood. Accordingly, we may suggest that alpaca fibers could be used for monitoring exposure especially to non-essential metals like aluminum, cadmium, and lead, and could constitute a suitable non-invasive method for measuring trace and non-trace element exposure in camelids.     

Nutrient concentration and yield of maize (Zea mays L.) after vetch (Vicia sativa L.) in conventional and reduced tillage systems

The effects of tillage on plant availability nutrients are critical to develop nutrient management strategies to optimize yield. The objective of this study was to evaluate differences in the concentration of 19-nutrient and yield after 4-year of conventional [moldboard plough (MT)] and two reduced [rototiller (ST) and chisel (CT)] tillage systems in maize (Zea mays L.) after winter vetch (Vicia sativa L.) in double crop one year. Three tillage systems were compared from 2005 to 2008 in area located in the western region of Turkey under semi-arid Mediterranean clay-loam soils. Nutrients were determined in maize leaves, stems, roots and soils. Results show that the concentration of macronutrients were found to be higher in leaves and stems of maize than roots in three tillage systems of all years, while the opposite was true for micronutrients. Among the macro and micro-nutrients, there was no effect of tillage on nutrient concentration in all maize tissues for sulfur, magnesium, sodium and copper (S, Mg, Na and Cu). However, the nitrogen, potassium, calcium, boron, zinc, manganese, iron, aluminum, barium, cadmium, cobalt, chromium, nickel, lead and selenium (N, K, Ca, B, Zn, Mn, Fe, Al, Ba, Cd, Co, Cr, Ni, Pb and Se) were affected by tillage. ST increased N in stems of 2006 compared with other systems. K in roots of 2006 was 52 and 30% greater in CT than in ST and MT, respectively, while ST and MT of 2007 resulted in 38 and 41% greater than CT. In two of four years, ST contributed to higher grain yield compared with other systems. In general, ST can effectively contribute to increase maize yield following winter vetch compared with MT under this region. Results suggested the need for different management systems associated with reduced tillage including rotation, particularly for basic nutrients. Further, results showed similarities and differences with other studies under tillage with maize following winter vetch.     

Effect of cultivar and processing method on the contents of polyphenols in table olives

Polyphenols were determined by HPLC in the juice and oil of packed table olives. The phenolic compositions of the two phases were very different, hydroxytyrosol and tyrosol being the main polyphenols in olive juice and tyrosol acetate, hydroxtyrosol acetate, hydroxytyrosol, tyrosol, and lignans (1-acetoxypinoresinol and pinoresinol) in oil. The type of processing had a marked influence on the concentration of polyphenols in olive juice and little on the content in oil. The analyses carried out on 48 samples showed that turning color olives in brine had the highest concentration in polyphenols ( approximately 1200 mg/kg), whereas oxidized olives had the lowest ( approximately 200 mg/kg). Among olive cultivars, Manzanilla had a higher concentration than Hojiblanca and Gordal. The type of olive presentation also influenced the concentration of polyphenols in olives, decreasing in the order plain > pitted > stuffed. The results obtained in this work indicate that table olives can be considered a good source of phenolic antioxidants, although their concentration depends on olive cultivar and processing method.     

Identification and quantification of metallo-chlorophyll complexes in bright green table olives by high-performance liquid chromatrography-mass spectrometry quadrupole/time-of-flight

Five different samples of table olives, two regular Spanish table olives and three "bright green table olives", have been analyzed by HPLC-MS/MS to determine their pigment profile. Typical pigment profiles of almost all table olives show primarily chlorophyll derivatives lacking metals (e.g., pheophytin a/b and 15(2)-Me-phytol-chlorin e(6)). Bright green table olives have a unique profile including metallo-chlorophyll complexes (Cu-15(2)-Me-phytol-chlorin e(6) with 26-48% and Cu-pheophytin a with 3-18%) as their major pigments. New tentative structures have been identified by MS such as 15(2)-Me-phytol-rhodin g(7), 15(2)-Me-phytol-chlorin e(6), 15(2)-Me-phytol-isochlorin e(4), Cu-15(2)-Me-phytol-rhodin g(7), Cu-15(2)-Me-phytol-chlorin e(6), and Cu-15(2)-Me-phytol-isochlorin e(4), and new MS/MS fragmentation patterns are reported for Cu-15(2)-Me-phytol-rhodin g(7), Cu-15(2)-Me-phytol-chlorin e(6), Cu-pheophytin b, Cu-pheophytin a, Cu-pyropheophytin b, and Cu-pyropheophytin a. The presence of metallo-chlorophyll derivatives is responsible for the intense color of bright green table olives, but these metallo-chlorophyll complexes may be regarded as a "green staining" defect that is unacceptable to consumers.     

Influence of Silicon on Sunflower Cultivars under Drought Stress,II: Essential and Nonessential Element Uptake determined by Polarized Energy Dispersive X‐ray Fluorescence

Abstract: There is no information regarding genotypic variation in essential and nonessential nutrient accumulation of sunflower grown under drought stress with the presence or absence of supplemental silicon (Si) despite the role of this element in improving growth of some cultivars under drought conditions. Accumulation of elements in sunflower cultivars might be important for the genetic improvement of the crop's response to drought. An experiment under controlled conditions was carried out to study the genotypic response of 12 sunflower (Helianthus annuus L.) cultivars to drought and Si and the relationship to the uptake of elements [phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn), chloride (Cl), molybdenum (Mo), Si, sodium (Na), vanadium (V), aluminum (Al), strontium (Sr), rubidium (Rb), titanium (Ti), chromium (Cr), nickel (Ni), bromine (Br), and barium (Ba)]. This was determined by polarized energy‐dispersive X‐ray fluorescence (PEDXRF). It was observed that uptake of nutrient and nonessential elements by sunflower cultivars were differentiated in response to applied Si and drought stress. Drought stress decreased mineral uptake of all the cultivars, and generally, application of Si under drought stress significantly improved Si, K, S, Mg, Fe, Cu, Mn, Na, Cl, V, Al, Sr, Rb, Ti, Cr, and Ba uptake whereas Zn, Mo, Ni, and Br uptake were not affected.     

Characterization of odor-active compounds in extracts obtained by simultaneous extraction/distillation from moroccan black olives

"Greek-style" Moroccan black table olives were screened for potent odorants by GC/olfactometry/aroma extract dilution analysis of representative Likens-Nickerson extracts and compared with "Spanish-style" green fruits. ( Z)-3-Hexenal, ( E, E)-2,4-decadienal, ( E, Z)-2,4-decadienal, guaiacol, and methional were found in both green and black olives, but with significant differences in concentration according to the fruit ripening degree (the first was lower and the last two were higher in black fruits). Specific compounds not previously detected in green olives (gamma-deca- and dodecalactones, delta-decalactone, and 2-methyl-3-furanthiol) proved to be, with methional, the strongest odors in black olive extracts. These extracts were also distinguishable from green olive extracts by the presence of new sulfur compounds and fewer terpenes.     

Chemometric classification of the fat residues from the conditioning operations of table olive processing, based on their minor components

The work characterizes the unsaponifiable matter of fats released in pitting green (GP) and ripe (RP) olives, in pitting/stuffing green olives with vegetable (GPSV) and animal (GPSA) products and in the fat settled at the end of the factory sewer system (W). The unsaponifiable matter ranged from 1.94% (RP) to 5.91% (GPSA); total sterols from 1319 mg/kg fat (GPSV) to 2002 mg/kg fat (RP), with β-sitosterol as the most abundant. Fatty alcohols ranged from 242 mg/kg (GP) to 556 mg/kg (W), with C22 as the most abundant. Triterpene diols were found only in GPSV (erythrodiol + uvaol, 0.80%). Wax was not present in the fats from GP and RP but increased with the general fat degradation in the order GPSV (128 mg/kg), GPSA (171 mg/kg) and W (263 mg/kg). Chemometric analysis was able to detect differences among the diverse fats; sterols + fatty alcohols cluster analysis was useful for fat grouping.     

水稻种植模式对水稻籽粒离子组的影响

亚细胞、细胞、器官乃至有机体内所有矿质元素的组合称为离子组。离子组是植物化学元素指纹,能够定量、精准地反映环境因子驱动下植物体产生的无机化学响应。为探求不同种植模式对水稻籽粒离子组的影响,采用大田试验,研究比较了长期常规种植、绿色蛙稻和有机蛙稻3种水稻种植模式水稻籽粒中矿质元素含量的差异和元素间的相关关系,并探讨了土壤中可利用态元素向水稻籽粒中的转移效率。21种元素含量通过高通量元素分析电感耦合等离子体质谱仪(ICP-MS)测定,并利用主成分分析和方差分析等统计方法分别对数据进行综合分析和各元素处理间差异分析。结果表明,各元素在水稻籽粒中的浓度顺序为:KPMgCaMnZnFeCuRbNaBaMoBNiSrAsCrCdSeCoCs。主成分分析结果表明,不同水稻种植模式对水稻籽粒离子组有显著影响,第1主成分占总变量的32.7%,区分了有机和绿色种植模式;第2主成分占总变量的27.1%,将常规种植模式和另外两种模式区分开。不同水稻种植模式对水稻籽粒离子组有显著影响。与常规种植相比,绿色蛙稻模式下籽粒第1主族元素K、Na、Cs、Rb含量显著增加21%、31%、59%、72%,Mn、Cd的含量显著增加23%、441%,B和Cr的含量显著降低63%和51%;有机模式下水稻籽粒中Co、Ni和Cd含量分别增加60%、286%和488%,而Ca、B、Mo、Sr和Cr的含量显著降低38%、60%、20%、27%和96%,而同主族元素间的竞争并未发现。因此,从水稻必需元素吸收角度出发,绿色蛙稻种植模式优于有机和常规种植模式;但绿色和有机蛙稻种植模式对一些非必需元素的吸收也为水稻食品安全带来隐患。因此,科学的养分管理和合理种植结构的调整对保证水稻食品的安全有非常重要的意义和价值。     

Multivariate analysis for the evaluation of fiber, sugars, and organic acids in commercial presentations of table olives

Table olives constitute an important part of the Mediterranean diet and the diet of many non-olive-producing countries. The aim of this work was to determine the fiber, sugar, and organic acid contents in Spanish commercial presentations of table olives and characterize them by means of a multivariate analysis. The selection of variables was carried out on the basis of a canonical analysis and their classification, according to processing styles and cultivars, through a linear discriminant analysis. Values of dietary fiber in table olives ranged from 2 to 5 g/100 g edible portion (e.p.). Some stuffing materials (almond, hot red pepper, and hazelnut) or the addition of capers produced a significant increase in the total dietary fiber in green olives. Glucose, fructose, and mannitol were usually found in the ranges of 0-55, 0-70, and 0-107 mg/100 g e.p., respectively. Succinic acid was detected only in green and directly brined olives (0-40 mg/100 g e.p.), while lactic and acetic acids were used within the ranges of 0-681 and 5-492.8 mg/100 g e.p., respectively. A multivariate analysis showed that fiber, mannitol, and succinic, lactic, and acetic acids can be used to discriminate between processing styles (95.5% correct assignations) and cultivars (61.20%). Current data can also be used in the evaluation of the dietary value of table olives.     

Effect of wastewater irrigation on mineral com‐position of corn and sorghum plants in a pot experiment

Effect of wastewater irrigation was investigated on mineral composition of corn and sorghum plants in a pot experiment. The ranges for the concentration of different minerals in corn plants were 0.67–0.89% calcium (Ca), 0.38–0.58% magnesium (Mg), 0.09–1.29% sodium (Na), 0.81–1.87% nitrogen (N), 1.81–2.27% potassium (K), 0.12–0.16% phosphorus (P), 190–257 mg/kg iron (Fe), 3.5–5.6 mg/kg copper (Cu), 37.1–44.5 mg/kg manganese (Mn), 21.6–33.6 mg/kg zinc (Zn), 1.40–1.84 mg/kg molydbenum (Mo), 11.0–45.7 mg/kg lead (Pb), and 2.5–10.8 mg/kg nickel (Ni). Whereas for sorghum plants, the ranges were: 0.56–0.68% Ca, 0.19–0.32% Mg, 0.02–0.27% Na, 0.69–1.53% N, 1.40–1.89% K, 0.10–0.14% P, 190–320 mg/kg Fe, 3.8–6.0 mg/kg Cu, 29.2–37.6 mg/kg Mn, 21.1–29.9 mg/kg Zn, 2.2–3.7 mg/kg Mo, 12.3–59.0 mg/kg Pb, and 2.5–15.2 mg/kg Ni. Heavy metals such as cobalt (Co) and cadmium (Cd) were below detection limits at mg/kg levels. The concentrations of Ca, N, K, P, Cu, and Mn in corn plants were in the deficient range except for Mg, Fe, Zn, and Al. The concentrations of Ca, N, P, K, Cu, Mn, Mg, and Zn in sorghum plants were in the deficient range except for Fe and aluminum (Al). The analysis of regression indicated a strong interaction between Pb, Ni, Ca, and Fe in corn and sorghum plants. In conclusion, waste water irrigation did not increase mineral concentrations of either macro‐ and micro‐elements or heavy trace metals in corn and sorghum plants to hazardous limits according to the established standards and could be used safely for crop irrigation.     

柴达木农田土壤Cd的积累影响及风险预测

【目的】土壤重金属空间结构特征是土壤环境质量评价及重金属污染评价的基础。本文用地质统计学方法研究了柴达木盆地原生地和耕种50年的农田土壤镉的空间分布特征,对土壤镉进行质量评价,同时分析了农业耕种对土壤镉积累的影响,调查统计了灌溉水、肥料、农药等农业源土壤镉的输入量,为农田镉积累的风险预测提供参考。【方法】以柴达木盆地诺木洪农场的一块原生地（从未耕种过的土地,可以认为无化肥污染）和一块耕种地（已种植了50年的农田）为研究对象,从原生地采集22个土壤样本,耕种地采集50个土壤样本进行镉含量的测定,同时检测灌溉水、农药、化肥中的镉含量,并进行每年农田输入量的统计。用Excel软件进行数据处理,反比权重法（IDW,Inverse Distance Weighting）插值,GIS9.3进行空间分析和图像处理;以单项污染指数法评价土壤镉质量,评价模式为Pi=Ci/Si（Pi为污染物镉的单项污染指数,Ci为污染物镉的实测数据,Si为污染物的评价标准）。评价标准分别以农业部公布的行业标准《无公害食品 枸杞生产技术规程》（NY/T 5249-2004）和《绿色食品 枸杞》（NY/T1051-2006）产地环境标准要求下的《绿色食品 产地环境技术条件》（NY/T 391-2000）为依据。依据农业源土壤镉输入量,以土壤现状值为起点,以绿色食品标准限量值为终点,测算输入量积累突破两端差值的年限。【结果】原生地22个土壤样品的镉平均含量为0.30 mg/kg,是土壤背景值的两倍（0.14 mg/kg）,达到无公害食品（0.60 mg/kg）和绿色食品（0.40 mg/kg）标准;种植50年农田的50个土壤样品的镉平均含量为0.43 mg/kg,是土壤背景值的3倍,达到无公害食品标准,但超过绿色食品标准。用于灌溉的河水的镉含量为0.0036 ng/kg。检测生产中使用的15种农药和7种肥料,其中的镉导致每年土壤镉增加3444 mg/hm2。最严重的污染源是鸡粪,施入土壤后每年导致土壤镉增加2025 mg/hm2,其次依次为复合肥（使土壤镉增加576 mg/hm2）,磷酸二铵（增加432 mg/hm2）,有机肥（增加360 mg/hm2）。【结论】以小尺度空间分布和全量统计研究的诺木洪农场土壤镉含量这一单一指标衡量,可以看出诺木洪原生地土壤是清洁的,能够满足无公害、绿色食品的生产;但是研究选择的多年耕种田已经遭到重金属镉的污染,只能达到无公害食品标准,而达不到绿色食品标准。现行生产中的施肥措施是导致诺木洪土壤重金属镉污染的一个重要因素,其中鸡粪对镉污染的贡献最大,其次是复合肥、磷酸二铵和有机肥。如果继续现在这种耕种方式,以现有的原生地镉含量均值为0.30 mg/kg进行计算,76.3年后该土地镉含量将超过0.40 mg/kg的绿色标准上限。     

Foliage Age and Pollution Alter Content of Phenolic Compounds and Chemical Elements in Pinus nigra Needles

Changes of phenolics and chemical elements [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), iron (Fe), boron (B), copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and cobalt (Co)] content in needles of black pine ( Pinus nigra) as dependent on age of needles (5–6 classes) and pollution were examined. The content of ortho-diphenols (o-dPh) and total phenols (TPh) was significantly higher at a polluted site than at a control one. It increased with age of needles at both sites. At the polluted site contents of N, K, Mg in black pine needles were lower and of Fe, Ni and F were higher than at the control site. An increase of content with age of needles at both sites was detected for Ca, Fe, B and F, and a decrease for N, P, K, Cu and Ni. The content of elements in different age classes of needles is connected with their mobility. The content of phenolics is negatively correlated with main nutrients and positively with some toxic elements.